Hugh Jackman led an all-star rendition of “Happy Birthday” for Amanda Seyfried Sunday following a screening of “Les Misérables,” and he even threw in a lap dance. Also singing for Seyfried — who was presented with a cake while standing on a chair at Porter House New York — were co-stars Anne Hathaway, Russell Crowe, Sacha Baron Cohen, Eddie Redmayne and Samantha Barks. Before shimmying, Jackman joked, “The last person I gave a lap dance to was Barbara Walters. I promised her not to ever give anyone else a lap dance. But she isn’t here tonight so she won’t ever know!” Anna Wintour was spotted “smiling through Jackman’s entire routine,” but one female guest hoping for more exclaimed afterward, “He didn’t give much of a lap dance.” Then again, the Peggy Siegal Company party for director Tom Hooper’s musical was a bit more upscale than all that, with guests including Universal’s Ron Meyer, Adam Fogelson and Donna Langley, producer Cameron Mackintosh, Chelsea Clinton, Sharon Stone, Brooke Shields, Michael Kors, Lily Rabe and Joan Collins, who was spotted “deeply engrossed in conversation with Hathaway.” The film screened at the AMC Loews Lincoln Square 13.